Access specific row col of a query tag in another tag

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1

Hi,
If I have a query tag which return a dataset, how can I reference other tag to specific row and col of this tag? (For example by an expression tag)

Imagine the query tag return 100000 rows which each row value is related to a tag.
So instead of sending 100k request to the DB I only read all data in a single query and assign them in ignition memory.

2

It is a good plan for efficient database access. I would use a gateway tag change event to loop through the new dataset whenever it arrives, assembling a list of memory tag updates to apply with writeBlocking().

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3

@nader.chinichian, I have been using lookup expression function to assign values to memory tags via a UDT. However, this is on a much smaller dataset. I can see this being a pain if your tags are not generic.

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